oday, we are not here as scientists or doctors. We are here as parents. Parents of a girl named Lucía. And like so many families, our story is one of love, fear, resilience—and, above all, hope.
First Symptoms and Diagnosis
Our daughter Lucía is a 10-year-old girl from Barcelona. She initially had normal development; in fact, she started talking and walking very early. In nursery school, she stood out: sharp, independent, determined to do things her own way, picking her own clothes, dressing herself. Very sociable but … with a strong character. People even suggested she might be gifted.
And yet something didn’t add up. We didn’t know anything about her disease, but we began to notice small, confusing signs:
- At the playground, she would often just watch other kids play. We thought she was simply curious. We jokingly called her “The Observer.”
- She sometimes seemed not to pay attention. As first-time parents, we didn’t recognize this as a signal that something might be wrong. More than once, people called her “rude.” As a parent, that hurts —you wonder what you’re doing wrong.
- The COVID-19 pandemic hid some of the symptoms, and we blamed other changes on the lockdown. It also acted as a trigger for what would come. Like other children, she had to attend online school and, truthfully, she wasn’t interested. She was only four, so we didn’t worry: “She’s little,” we thought. Her teacher told us she needed strong adult support. We didn’t take it very seriously. It was a hard time for everyone, especially very young children confined indoors with no chance to play outside.
- When we were finally allowed to travel, we went to my parents’ home. There we began to see that Lucía’s behavior was excessively difficult: She got angry, spoke rudely to her grandparents, didn’t listen when scolded, didn’t follow instructions—constantly testing limits. We were worried, but we wrote it off as the emotional toll of confinement.
- And then one day, at a crosswalk, despite her father’s warnings, she didn’t stop and was nearly hit by a car. At 4 or 5 years old, children understand danger. She didn’t seem to.
My husband insisted we look for answers to these small signs. I thought he was exaggerating, that she had simply suffered through too many restrictions and it was a maturity issue. He had a conviction that was hard for him to explain: “Something isn’t right,” he kept telling me.
The first genetic tests were inconclusive. We heard ADHD, maybe dyslexia or autism spectrum disorder—but it was too early to confirm anything.
We started ADHD medication. The doctor was clear: If it’s ADHD, the medication will help; if nothing changes, it likely isn’t ADHD. We had no choice but to try. Lucía lost a lot of weight, slept poorly, and her temper worsened.
An EEG suggested signs of epilepsy, though she’d never had a seizure. We started anti-epileptics. Months later, after a second MRI, we were told Lucía had cerebellar atrophy that needed further study. Each specialist referred us to another. Each test brought new questions, not answers.
After several months, we returned for routine follow-up with the neuropediatrician. He was worried by what we reported: Behavioral issues, regression in language, echolalia (repeating the last word she heard), severe difficulty reading and writing. What she had learned seemed to be slipping away. Clearly, something was wrong.
And then, after a second, more extensive genetic test—an exome, whose results we waited nearly six months for—we heard a word we had never encountered: Neuronal Ceroid Lipofuscinosis, CLN5 variant—better known as Batten disease, CLN5.
We will never forget the day we were told: October 3, 2023. Lucía had just turned eight, the day our world collapsed.
Her neurologist asked an assistant to take Lucía to another room. His face said it all. “I don’t have good news,” he told us. “I’m very sorry. Lucía has a genetic, ultrarare, neurodegenerative disease that primarily affects the nervous system and, as of today, has no approved treatment or cure.”
Before giving us the diagnosis, he had already checked if there was a clinical trial we might access. Fortunately, there was one recruiting patients at that time. He contacted the study sponsor before our visit. They were in the middle of screening for the last children to enter the study and seemed to have enough candidates already.
We asked him what the disease meant. He said it affected the nervous system, progressively taking away abilities. I don’t think he told us, to be blunt, that it would affect every sphere of life: walking, speech, vision, swallowing, even breathing independently; that it would bring dementia, cognitive and motor decline, seizures, sleep issues, and behavioral problems. He focused on hope. There was a trial and we had to get Lucía in it any way we could.
Inevitably, I asked the question no parent wants answered: “Does this mean our daughter is going to die? How long does she have? What can we do?” He told us he didn’t know. It’s such a rare disease that there isn’t much literature. The natural history was unclear. While everything pointed to a short prognosis after diagnosis, he couldn’t confirm what we desperately wanted to know.
After the hardest moment of our lives, I remember looking at our daughter as she came back into the room, smiling at that very instant, and thinking: “How can she be so full of life when we’ve just been told her life will be so short? How will we bear watching our daughter slowly disintegrate?” Life changes in seconds. Ours had spun 360 degrees. You enter a world you never asked for, never knew existed, and one you cannot leave.
Life After Diagnosis: A Sliver of Hope
After diagnosis, we threw ourselves into understanding. CLN5 disease is an inherited, progressive, neurodegenerative lysosomal storage disorder that belongs to a group of disorders called the neuronal ceroid lipofuscinoses (NCLs), collectively known as Batten disease. Children with CLN5 often develop normally until around age 5, when the first signs appear: Subtle movement difficulties that look like clumsiness, loss of previously acquired motor skills, recurrent seizures, ataxia, significant vision loss, speech problems, and cognitive decline. It is progressive. There is currently no approved therapy.
It became my obsession. There had to be something that could help. I started reading scientific papers, barely understanding but desperate to learn. We could not stop trying to get Lucía into the only clinical trial. It was our only hope.
We were, in that sense, fortunate. Of all Batten variants, there was an ongoing trial of a promising gene therapy trial for Lucía’s specific variant.
We decided to contact the sponsor ourselves. One week after diagnosis, we had a first call with the sponsor’s patient advocacy team, who told us that five children were ahead of Lucía for eligibility screening. Since the previous year, three children had already been treated; three more would enter this first phase (phase 1/2). Our chances didn’t look good. Children didn’t enter simultaneously; months (or years) could pass before a slot opened. They strongly encouraged us to contact the trial sites and the primary investigators. There were two sites: London and New York.
A few days later, we spoke first with the London lead investigator and then with the New York site. They explained that the disease was extremely rare; eligible candidates were hard to find. Globally, there might be only about 30 known children and they were struggling to identify those suitable for treatment. They were particularly interested in very early-stage cases.
From the outset, they were clear: this was experimental. We needed to weigh the risks, which they explained in detail. But what other option did we have? Given the disease’s progression and its fatal outcome, we had no choice but to participate if offered—and accept any risk. It had become a matter of life or death.
There were understandable coordination hiccups between sites: London proposed preliminary tests; New York suggested going straight to screening and, if all was well, to treatment. For us, any door was a ray of light. We would go to London, to New York, if it gave Lucía a chance.
In February 2024, the investigator from the London site contacted us: Lucía could come to London for pre-screening in March—on my birthday. What better gift than to see our daughter considered for a promising clinical trial? A door was opening.
After passing pre-screening, we were called to return to London for screening on May 11. If Lucía passed, she would receive treatment and we would need to stay in London until mid-January the following year. If not, we’d be back home in six weeks.
We began Operation Move. Organizing a family of four “just in case” is not easy. How would we pause our lives for eight months? We rushed to arrange visas for what we hoped would be a long stay.
A few days later, she was scheduled for what we thought was the key test: confirming she had no antibodies to the AAV vector. A positive result would exclude her automatically. We were confident about the rest, as Lucía was still very early-stage. Those antibody results would take three to four weeks.
All tests took place at the Great Ormond Street Hospital (GOSH) Clinical Research Facility, newly renovated to make participation more comfortable for children. We felt supported and cared for, despite the circumstances.
Good news! The AAV antibody test was negative. However, other results showed a recent infection—not an explicit exclusion criterion, but still a concern.
Finally, after days of uncertainty, fear, and frayed nerves, on June 14 we were told that Lucía could receive treatment. She was eligible for an investigational gene therapy designed to address neurodegeneration and vision loss in CLN5 Batten disease. She would be the last child treated in London and would receive the high dose.
We cried with joy. Our daughter had a chance.
Treatment was scheduled for July 10, followed by baseline assessments, preparation, and immunosuppression. The treatment procedure went well: 24 hours in ICU, then to the ward. We were amazed at how quickly she recovered. For safety, we stayed a few extra days, then were discharged home.
Post-Treatment
At first, we made frequent hospital visits for steroid and therapy monitoring, and ophthalmology checks (to follow the treated eye).
The immunosuppressants were very hard on Lucía. Some medications brought side effects: Aggressive behavior, voracious hunger, disturbed sleep. She was angry (mostly with me) for no clear reason, screaming, anxious, sometimes hitting, obsessed with food. It was hard to plan activities she could enjoy because nothing seemed to interest her. Far from home, in a different language and environment, everything was harder.
Emotionally and psychologically, we struggled. We lacked the support of family and friends. We were receiving excellent medical care but without our social network, alone in a foreign country. Schooling in a foreign country wasn’t easy. Communication was difficult. School kept her “occupied” a few hours, but alignment and understanding were not simple or easy.
Points of Light
Still, there were lights. Despite the difficulties, our whole family grew stronger together and got to know each other in new ways. We had time together we never would have had with our routines in Spain. And I fear Lucía would not have been as closely monitored in Spain as she was as a participant of a clinical trial. Of course, she had her school, her neurologist and pediatrician, and our family and friends in Spain, but in London she was cared for all the time.
Our interactions with the GOSH medical teams and study staff were outstanding. They listened whenever we had doubts about post-treatment side effects, checked with the sponsor, and guided us on whether to maintain or reduce doses. They supported us deeply. They even proposed consultations with psychiatry and rare-disease neuropsychology teams to help us manage Lucía’s behavioral issues and our own emotional state, which we deeply appreciate. This specific detail wasn’t part of the clinical trial.
Lessons for Regulators and Industry
With time and perspective, now that we’ve been home a few months, and speaking with the utmost respect: We are profoundly grateful for the opportunity to participate, and for the competence and humanity of the healthcare teams. Precisely because we value this, we propose these concrete improvements for clinical trials:
Transparency of patient’s clinical information: In our case, most of the test results were not shared and Lucía’s neurologist in Barcelona lacked data for ongoing care. Back home, we had to repeat tests (MRIs under anesthesia) that exposed Lucía to unnecessary risks. We understand trial confidentiality, but protecting a child’s health requires a structured, safe clinical handover between research and care.
Communication between parties: Information flow with our local doctor was insufficient during and after the study. We—the parents, without medical training—became the messengers. Formal meetings between trial clinicians and local care teams at key milestones are essential for better continuity of care.
Discharge letter and follow-up plan: We did not receive a detailed discharge summary for Lucía’s doctor in Spain. Experimental trial results may be confidential, but there should be a minimum exit package: Procedures performed, clinically relevant results, safety red flags, therapeutic guidance (if any), and a follow-up timetable. Again, parents are not equipped to transmit medical information accurately.
Testing burden and logistics: In pediatrics, the burden is not only scientific—it is human. Many tests are tough for children like Lucía. We know protocols have requirements but consider clustering tests into fewer days, avoiding duplications, and preserving, as much as possible, a “normal” life for the child. Long hospital days, weekly repeated ophthalmology exams, multiple blood tests (some very early in the morning) are exhausting.
Support for the child during clinical interviews: The child should not be present while parents speak with the trial team, to potentially hear distressing content or interrupt from boredom or anxiety. Holding medical interviews in a foreign language under these conditions is very hard. GOSH has excellent volunteers, play specialists, entertainers, and therapy dogs to assist in these circumstances; we suggest institutionalizing protected blocks of time with programmed recreational support for the child during technical interviews.
Post-treatment monitoring: We believe parts of the follow-up could have been shortened or decentralized and propose exploring hybrid models, such as conducting certain tests at the local hospital under sponsor agreement and oversight whenever safety allows.
It is hard to be abroad—alone, unable to work, with minimal help—for months. We are immensely grateful for the opportunity, but it left us tired and emotionally worn. It was a true trial by fire for our family. The disease is already that—being alone abroad made it even harder.
Interpreter and daily life: Language is no small matter. An interpreter is absolutely necessary for families who don’t speak the local language, not only for medical visits but for daily life in a foreign country. Formal access to interpreters and cultural mediators will help displaced families.
Communication about critical trial decisions: We learned that the trial had been paused on the internet. This decision did not affect our daughter, who had already been treated. But it must have been devastating for those awaiting trial progress for future treatment. It may be common practice, but it is not acceptable for participants to learn of a suspension/termination online instead of from the sponsor. If a decision is made to pause, delay, or end a trial, the primary stakeholders—participants—should be informed before any public notice.
Global Context of Rare Diseases
Our story is personal, but part of a much larger reality:
- More than 7,000 identified rare diseases worldwide.
- More than 300 million people affected.
- And 95% have no approved treatment…
Not because they are impossible to treat but because rare disease patient populations are small and thus deemed not “profitable.” Tell that to a parent watching their child lose abilities day by day.
We understand that drug development is complex. It takes years, investment, and international collaboration. But we also know that when humanity decides to prioritize something, extraordinary things happen.
COVID-19 vaccines were developed in under a year because the world made it a priority. Why not bring that same urgency to rare diseases?
There is innovation (such as gene therapies, CRISPR, AI in research), but innovation means little if it doesn’t reach patients. If it doesn’t reach the child who needs it, it remains an idea—not a solution.
Time is Precious
Our months in London taught us two key things:
- The scientific community has enormous talent and dedication.
- The barrier is not will or knowledge—it is resources, investment, and priorities.
All families like ours want is time.
Time to slow the disease.
Time to preserve abilities a little longer.
Time to make memories.
This is why collaboration is essential. When one family raises awareness, it helps another family somewhere else. When one country funds a trial, it creates knowledge that may benefit everyone. No effort in rare disease research is wasted because behind every data point, every paper, every experiment, there are real children like Lucía waiting.
What Do We Need?
We need visibility.
Without visibility, there is no funding.
Without funding, there is no research.
Without research, there is no cure.
We need patients and their caregivers involved in clinical trial design. Keeping patients at the heart of decision-making matters. Their essential knowledge and lived experience can—MUST—improve trial design and health policy.
We need innovation and access. Therapies and clinical trials cannot remain only in journal articles. They must reach patients quickly and fairly, with more agile and flexible regulatory pathways. For ultrarare pediatric conditions, create accelerated approval frameworks based on reasonable evidence and robust post-authorization follow-up. We are not asking for arbitrary exceptions. We ask for proportionality of risk against the alternative: confirmed degeneration. If profitability is the barrier for populations of 20 to 40 children worldwide (as in Lucía’s case), design risk-sharing mechanisms and European/transnational funds for ultrarare pediatric gene therapies.
We need international collaboration and cross-border solutions. Facilitate medical visas, temporary schooling, and housing referral agreements, and establish safe decentralization routes such as local tests audited by sponsors to reduce forced, months-long stays away from home.
We need clinical data transparency and sharing. A minimum standard of interoperability between trial sites and local clinicians must include discharge summaries, transferable results, safety alerts, and schedules. Trial confidentiality must not become a firewall against a child’s ongoing care.
We need responsible communication. For critical changes (pauses, suspensions, no-go decisions), inform families first—with time and psychosocial support—before releasing any public announcement.
Time is the most critical factor in rare diseases. With each passing day, children lose abilities they will never recover. And as parents, witnessing that is unbearable.
“No treatment, no cure”
No parent should ever hear these words about their child or be expected to take their child home and told to enjoy the time they have left. Regulators and industry must act with urgency on drugs for rare diseases. Let’s not let process slow down progress.
To Get There, We Need You All
Despite everything, Lucía keeps smiling. Every day, her laughter reminds us why we fight not only for her but for every child like her.
- Regulators: Chart pathways that balance risk and urgency for tiny populations, where every month counts.
- Industry: Commit to viable patient-centered designs and models that make possible tomorrow what seems uneconomic today.
- Scientists: Keep pushing the limits with rigor and methodological creativity.
- Hospitals and clinical teams: Strengthen the interoperability and humanized care you already practice.
- Patient organizations: Remain a central voice, not a token presence.
- EU Member States: Invest in health and education so these treatments become viable.
- The European Union: Ensure that these children are not discriminated against as a minority.
Let’s run faster than Batten.
Because every day counts.
Every child counts.
And no child is too rare to matter.